A quote from the article:

We require all of our suppliers to certify in writing that they use conflict-few materials,” wrote Apple chief Steve Jobs in response to consumer questions last summer. “But honestly there is no way for them to be sure. Until someone invents a way to chemically trace minerals from the source mine, it’s a very difficult problem.”

That seems a reasonable statement. I don’t see how Apple or any company could investigate their suppliers continuously. This seems a job for a governmental body.

via Conflict minerals: Genocide in your gadgets? – CSMonitor.com.